1. Field of the Invention
This invention relates generally to mattress assemblies and methods for rotating mattresses.
2. Discussion of the Prior
When a person repeatedly lies in the same location on a mattress, a body depression or cavity tends to develop in the materials of the mattress. Such body depressions typically result from a stretching of the mattress fabrics and a compression of the fill material associated with the mattress. Such body depressions are to be avoided since the stretched fabric tends to be unsightly and the compressed fill materials tend to create a relatively hard surface which interferes with sleep. Furthermore, the person sleeping on the mattress tends to lie in a recessed area which may not accommodate a preferred sleeping position providing the best support and comfort.
Body depressions are particularly noticeable when the mattress is shared by a couple. Under these conditions, the amount of area devoted to each individual tends to be reduced, so their sleeping habits are even more restricted to a given area. Furthermore, when two people are sleeping on the same mattress, their differences in weight may be most noticeable in their respective body depressions. Thus in a typical case, the body depression associated with a relatively heavier husband may be particularly severe compared to that of a relatively lighter wife.
In the past, attempts to relieve the stretching and compression associated with body depressions have required that the entire mattress be rotated. Turning the mattress on a vertical axis does not require that the mattress be lifted substantially, but this is still difficult particularly if the bed is located next to a wall. Flipping the mattress about a horizontal axis requires that the mattress be significantly elevated making this a most difficult task.
More recently mattresses of both the water bladder and innerspring coil variations have been constructed with pillow tops which tend to include a thin quilting of cotton or other fibrous materials. These pillow tops have been particularly susceptible to compression so that the body depressions have been even more objectionable in recent years.
Mattress systems such as that disclosed by MAGNUSSON in U.S. Pat. No. 4,449,261 have addressed the removal and rotation of mattress portions but for entirely different reasons. In this case, Magnusson discloses that a pillow top having two major surfaces can be constructed so that each surface presents a different hardness to the person sleeping thereon. Flipping the pillow top enables the person to select the desired degree of firmness. The means for attachment is disclosed to include hook and loop fasteners which facilitate the removal and rotation of the pillow top. Although sliding fasteners such as zippers have been mentioned in this context, there has been no appreciation that a special zipper configuration is required in order to accommodate the removal and rotation of the pillow top.